Learn about how public-sector scientists saved papaya

Friday, January 23, 2015

In the mid-1990s the papaya farmers of Hawaii were threatened with devastation by a newly rampant disease, papaya ringspot virus. Luckily scientists at the universities of Hawaii and Cornell were already working on the problem. Using the newly-invented technique of genetic modification, they used a genetic sequence from the virus and inserted it into the papaya genome. Analagous to vaccination in humans, this produced 100% virus-resistant plants.

The innovation came just in time - by 1998 production in Hawaii's main papaya-growing area had fallen to just half the 1992 level due to viral damage. Following safety trials the GM papaya was quickly cleared by regulators and seeds provided to Hawaiian growers at cost and without patent or other costly restrictions. This prompt action saved the industry and today a majority of Hawaiian papaya, including most of the fruits imported into the United States and Canada from the islands, is genetically modified to be virus resistant.

Buoyed by this success, Cornell scientists began working with researchers in other countries threatened by the disease. Top of the list was Thailand, where papaya is a national staple in the green salad dish som tam and was similarly threatend by the rapid spread of papaya ringspot virus. Thai government scientists transferred the resistance genes into Thai papaya varieties and began field trials.

Unfortunately at this stage, in July 2004, anti-GMO pressure groups intervened. Activists invaded and damaged the papaya trials, and spread scare stories in the national media.

The Thai government shut down the program, and forced the researchers to destroy and bury all their resistant papaya trees in pits at the trial site. Farmers growing GM papaya were tracked down and their trees destroyed. Thai papaya farmers were permanently deprived of access to this promising innovation, and Thai consumers were denied a source of virus-free fruit grown in their own country. Today Thailand's papaya industry is still severely affected by the virus, and production much lower than it would otherwise be.

Anti-GMO pressure groups have now circled back to Hawaii, sparking off a divisive political battle in the state to restrict or even forbid cultivation of all GM crops. Papaya farmers would be forced to register the location of GM papaya plants, making them a target for vandals, and making consumers fearful about a fruit many have already safely consumed for a decade.

If the these pressure groups succeed, Hawaiian papaya producers (most of whom are small-scale family farmers) may be denied access to the virus-resistant papaya they have already become dependent upon - harming their livelihoods and undermining many years of successful work.